The preliminary trip to Piraeus was a bust. Due to limitations of time (public transit ending at 6 p.m. tonight) & map (I didn't realize one place I was looking for was off my already-poor map), we returned to the central city without having done the complete dry run that we intended to.
However, if I can find a better map & if others are adventuresome, we'll do this again Sunday.

The plan for Piraeus is to check out the Sunday flea market, have lunch at
Margaro. walk around the Zea harbor (where Athens used to parked its triremes), coffee at
Cafe Freddo, then take the Metro back to Central Athens.